Introduction to Linux
rohitrawat@gmail.com
March 1, 2016
What is Linux
- Linux is an Operating System (OS) – the software that manages its processor, memory and devices and lets you run different programs on it. Other OSes include Microsoft Windows and MacOS.
- Linux is free and open source.
- It has been developed collaboratively by many developers across the globe making it extremely robust and transparent.
- It is the number one OS running on the Internet – Google, Facebook, Twitter, Wikipedia and many other sites run on Linux OS.
Why you might need Linux
- Software Engineers & System Administrators
- Large websites like Google/Facebook run on Linux
- Preferred programming environment
- Electrical Engineers
- Most hardware (Android phones, R-Pi, smart TVs..) run Linux
- Robotics and Control Engineers
- High performance computing
- Supercomputers and clusters run on Linux
Free Open Source
“Free as in freedom”
Software with source code available that you are free to study, change and distribute for any purpose. Examples GPL, BSD licenses.
“Standing on the shoulders of giants”
Imagine:
- Having to pay ridiculous amounts of money to start working on a new idea
- Not being unable to customize software to your needs
= stifled innovation!
Open Source in Your Life
- Major websites: Google, Facebook, Amazon, Twitter, Dropbox
- Software you use: Mozilla Firefox, Oracle Java, VLC, LibreOffice
- Android smartphones
- Embedded Linux devices: Smart TVs & DVRs, ATM machines, Wireless routers
Linux Awareness
- Why haven’t I heard of Linux before? Why did my laptop ship with Windows or MacOS?
- In its early days, it was actually difficult get some things running on Linux. You needed some expert help.
- There isn’t much awareness about Linux outside the IT community.
- Some hardware and software manufacturers provide software and support only for Windows.
Brief History of Operating Systems
- In early days, computers were large multi-user mainframes running some flavor of the Unix operating system (1969).
- Personal Computers (PC) started using MSDOS (1981-2000), transitioning to Windows later (1990).
- Mac-OS (1984) competed with Windows on Mac-PCs but Microsoft was always the bigger player . OS X was released in 2001 and is based on Unix (NeXTSTEP).
- Linux rose as a free Unix-”like” operating system now completely dominating the server market and becoming a popular PC OS. (1991-current)
Learning Linux
Outline:
- Linux distributions
- Command line and GUI interface
- Installation
- Basic Shell commands
Linux distributions
Most popular ones:
- Linux Mint
- Debian
- Ubuntu
- OpenSUSE
- Fedora
- CentOS
- Arch

Fedora

Ubuntu

Debian

Linux Mint

Command line

Installation
- Play safe - install in a Virtual Machine
- only a tiny bit slower than a full install
- no need to partition your hard drive
- no need to mess with boot menus
- you can easily launch Linux, pause it, resume it, keep it running in the background without exiting Windwos or your Windows programs!
- you can set up shared folders to share your My Document, Desktop or even your whole drive with the VM.
VM Installation instructions
Windows users download link: Windows
Mac OSX users download link: MacOS
Download the ISO image of a Linux distribution (Ubuntu Linux or Linux Mint is recommended)
Note: amd64 means any Intel or AMD CPU - don’t let that confuse you
More learning
- Watch these introductory videos on YouTube:
Next meeting

Try the shell
Go to the address shown. Login with the username and password on the piece of paper.
Commands
You can try these commands in your shell window:
- whoami - prints your username
- pwd - tells your location in the file system
- /home/username is your home directory
- ls - lists the files in the current directory
We can add switches to commands to change their behavior:
- For the ls command:
- ls -F - differentiates between files and folders
- ls -l - shows additional file details
- ls -l -t - combine -l and -t (sort by time) switches
- ls -F -a - shows hidden files
- the . means the current folder
- the *..** means the parent folder
- .bash_history stores your command history
- tree - displays the file system structure
Commands
The following commands do things, like changing your current directory, creating and copying files etc.
- Try: cd Desktop
- Then try: pwd
- Try: ls -F -a
- These are the files in the Desktop folder
- If you do: cd ..
- This will take you back to your home directory